Attachment for grinding machines



Dec 4, 1928. 1,694,074

J. MARTONE ATTACHMENT FOR GRINDING MACHINES Filed NOV. 14, 1925 ug-W INVENTOR BYH I ATTORNEY tferemz'ajz Mariana 1 Patented Dec. 4, 1928.

UNiTEDSTA-TES JEREMIAH MARTONE, or WATERBURY,"CONNECTICUT;

ATTACHMENT Eon GRINDING MACHINES.

Application filed November This invention relates to cutter grinding machines, and more particularly to a holding device for guiding a. spiral milling cutter while its teeth are being ground.

One object of this invention is to provide a device of the above nature which may be attached to the stationary bed of a grinding ma chine, and which will guide each of the teeth of the cutter in succession and cause them to be ground uniformly without removing the attachment from the machine.

A further obj cct is to provide a. work-holding attachment for a grinding machine which will have a double universal joint for rotary adjustment and means for allowing longitudinal adjust-menu A further object is to provide a device of this nature which will be simple in construction, inexpensive to manufacture, easy to install and manipulate, compact, and very efficient and durable in use.

\Vith these and other objects in view there has been illustrated on. the accompanying drawings, one form in which the invention may be conveniently embodied in practice.

Fig. 1 represents a side view in elevation of a grinding machine upon which the improved attachment has been installed.

'2 is a. side sectional view of the same, shown partly in section.

Referring now to the drawings, in which like reference numerals denote corresponding parts throughout the several views, the numeral 10 indicates the sliding lower table of a grinding machine, said table 10 being adapted to rest on a rotary bed, not shown, said bed beingcapable of vertical and rotatable movement with respect to the machine base, not shown.

The rotary grinding wheel 11 is rigidly mounted onthe base of the machine by means not shown and is constructed in saucer shape form. The grinding wheel 11 is carried bya shaft 12, the latter being driven by any suitable source of power, not shown. The top of I the grinding wheel is protected by a semi-circular guard member 13. l

A sliding upper table 14 is mounted upon the lower table 10, and is adapted to be reciprocated longitudinally by manually-controlled means, not shown. The sliding upper table 14 supports at its ends a. pivoted head stock 15 and a rigid tail stock 16, between the centers 17aud 18 of which a mandrel or arbor 19 is supported. The arbor '19 serves to sup- 14 192 5. Serial eases.

port the jworkto be ground, which in this instance comprises. a, milling cutter 20 having spiral teeth.

In order to hold the toothbeing ground in parallel contact with the grinding wheel, while the milling cutter is reciprocated back i and forth, a worleholding attachment is pro vided, and willnow be described.

The wvork l1olding attachment comprises a flat pedestal 21, adapted to be rigidly secured, as by a screw bolt/22, to the lowertable 10 of the machine. 'Upstanding from the pedestal 21 isa vertical post 23 which is preferablyfornied integral with said pedestal. A rod 24 is mounted to have rotative adjustment on a vertical as well ason a horizontal axis. I For this purpose, a lower clamping block 25 is'slidably held on said vertical-post 23, as

I by a bolt 26 and nut 27, said lower block 25 having a. projecting member 28 for slidably supporting the rod 24.

Slidably mounted on the top of therod 24 is an upper clamping block 29 similar to the lower block 25, previously described. The upper block 24has a pair of clamping aws 30 and 31 adapted to be tightly held upon a work-holding arm 32 by means of a bolt 33 and nut 34. A micrometer adjusting mechanism 35 is provided for moving the workguiding finger 36 toward and away from the milling cutter20. The micrometer mechani sm 35 is adapted to be manipulated by a knurled knob 37, The finger 36 is preferably made with a slightly curved extremity 38 which is adapted to fit against'the tooth next to the 7 one being ground. The rear portion of the finger 36 is secured as by a screw 39 to a strip member 40, resiliently mounted within a box member 41 within which it is free to vibrate on a pivot pin 42. p

The rear of said strip member 40 is pressed by a spring 43 which permits the finger to yield and release chips or other materials which might otherwise cause the cutter to be injured. The spring 43 also allows the finger to be bent up about its pivot to permit the I cutter to be rotated until the finger is in alinement with the next tooth without disturbing the adjustment of the work-holding at tachment. I

In operation, when it is desired to grind the teeth of the milling cutter, the work-guiding finger 36 willfirst be adjusted to fit into the tooth next to the first one to be ground. The proper angle of inclination corresponding to the pitch of the spiral cutter is obtained by manipulation of the double universal joint described above. The rotary bed will next be raised until the cutter is adjacent the grinding wheel which is stationary at this time, and th e.

face of the tooth will be brought into parallel contact with the face of the grinding wheel. The operator will then lower the rotary bed until the cutter is out of contact with the grinding wheel, and the power will then be turned on to rotate the grinding wheel at high speed. The thickness of cut will then be accurately gauged by turning the micrometer knob 37 to move the cutter the required angular distance toward the grinding wheel. To

obtain the first cut, the operator will raise the cutter the required distance and will slide the upper table and cutter along the grinding wheel until the entire length of the tooth has been cut. The-same cut will then be taken from all of the othercutter teeth. For the second cut the cutter will be raisedagain still further and the operation repeated-on all of the teeth. This process will be repeated until the desired depth of each tooth has been ground.

One advantage of the present invention is that the work-guiding finger may be positioned at any conceivableangle or height.

A further advantage is that the depth of cut may be adjusted after the correct angular position has been obtained and the former adjustment is independent of the latter. Moreover, this construction ermits the cutter to be fed toward the grin ing wheel witharm, a horizontal workout the use of a transversely fed table, which was formerly required.

While there has been disclosed in this specification one form in which the invention may be embodied, it is to be understood that this form is shown for the purpose of illustration only, and that the invention is not to be limited to the specific disclosure but may be modified and embodied in various other forms without departing from its spirit. In short, the invention includes all the modifications and embodiments coming within the scope of the following claim.

Having thus fully described the invention,

what is claimed as new, and for which it is desired to secure Letters Patent, is:

In a work-holder for guiding a spiral milling cutter while the latter is being ground by a rotatin grinder, a vertical post ada ted to be held stationary upon the lower tab e of the machine, a lower clamping block slidable vertically upon said post and carrying an JEREMIAH MARTQNE. 

